XI 


Bulletin  No.  21,  New  Series. 

U   S.  DEPARTMENT  OF  AGRICULTURE, 

DIVISION'  OF   ENTOMOLOGY. 


PRELIMINARY  REPORT 


Insect  Enemies  of  Forests  in  the  Northwest. 


AN  ACCOUNT  OF  THE  RESULTS  GAINED  FROM  A  RECONNAISSANCE 
TRIP  MADE  IN  THE  SPRING  AND  EARLY  SUMMER  OF  1899. 


PREPARED  UNDER  THE  DIRECTION  OF  THE  ENTOMOLOGIST 


A.    D.    HOPKINS,    Ph.   D., 

Vice-Director  and  Entomologist  of  the  West  Virginia 

Agricultural  Experiment  Station. 


WASHINGTON: 

GOVERNMENT    PRINTING    OFFICE. 

1899. 


MYlsios  OF  ENTOKOtOGY, 

Entomologist:  L  O.  Howard; 

First  Assistant  EntomoloyitL  ('.  1..  Marlatt. 

T!i.  Peig&nde,  F.  H.  Chittenden,  Frank  Benton. 
E.  A.  Bchwarz,  D.  W.  OoquiUett 
louts:  It.  S.  Clifton,  Nathan  Banks,  F.  C.  Pratt,  Ang.  Busck,  <>u«.  Heidemann, 
A.  N.  Candt'll,  J.  Kotinsky. 
Artist:   Miss  L.  Sullivan. 


Bulletin  No.  21,  New  Series. 

U.  S.  DEPARTMENT  OF  AGRICULTURE, 

DIVISION'  OF   ENTOMOLOG1 . 


PRELIMINARY   REPORT 


ON   THE 


Insect  Enemies  of  Forests  in  the  Northwest. 


AN  ACCOUNT  OF  THE  RESULTS  GAINED  FROM  A  RECONNAISSANCE 
TRIP  MADE  IN  THE  SPRING  AND  EARLY  SUMMER  OF  1899. 


PREPARED  UNDER  THE  DIRECTION  OF  THE  ENTOMOLOGIST 

BY 

A.    D.    HOPKINS,    Ph.    D., 

Vice-Director  and  Entomologist  of  the  West  Virginia 

Agricultural  Experiment  Station. 


WASHINGTON: 

GOVERNMENT    PRINTING     OFFICE. 
1899. 


LETTER  OF  TRANSMITTAL 


U.  S.  Department  of  Agriculture, 

Division  of  Entomology, 
Washington,  D.  C.,  October  18,  1899. 
Sir:  I  have  the  honor  to  transmit  herewith  manuscript  of  a  prelimi- 
nary report  upon  forest  conditions  as  relating  to  insect  work  in 
portions  of  the  States  of  Oregon,  Washington,  and  Idaho,  which  has 
been  prepared  by  Dr.  A.  D.  Hopkins,  of  the  West  Virginia  Agricul- 
tural Experiment  Station,  and  which  is  based  upon  observations  made 
by  him  under  commission  from  this  Division  during  April.  May,  and 
June  of  the  present  year.  Dr.  Hopkins  was  chosen  for  this  work  on 
account  of  his  great  knowledge  of  forest  insects,  a  subject  of  which 
he  has  made  a  special  study  for  a  number  of  years,  his  previous  obser- 
vations having  been  made  largely  in  the  State  of  West  Virginia.  The 
writer  considers  himself  fortunate  in  being  able  to  secure  Dr.  Hopkins's 
services  for  this  investigation,  and  feels  sure  that  the  results  obtained, 
even  as  displayed  in  this  preliminary  report,  will  be  of  value  to  the 
forest  interests  of  the  Northwest.  The  publication  of  this  report  as 
Bulletin  No.  21,  New  Series,  is  recommended. 

Respectfully,  L.  O.  Howard. 

Entomologist. 
Hon.  James  Wilson. 

Secretary  of  Agriculture. 

3 


PREFATORY  SOTE 

The  accompanying  preliminary  report  of  m\  investigations  of  insectfi 
[njurious  to  forests  ha  California,  Oregon,  Washington,  and  Idaho  is 
made  in  accordance  with  the  authorization  of  the  Secretary  of  Agri- 
culture, dated  March  30,  and  the  Letter  of  the  Entomologist,  dated 
April  1 1.  L899. 

Before  proceeding  further.  I  wish  to  express  grateful  acknowledg- 
ments t<>  all  those  w  h<>  have  in  any  way  assisted  me  in  this  work,  among 
whom  the  following  deserve  special  mention:  Messrs.  Pergande  and 
Busck,  for  tin-  excellent  care  of  the  breeding  material  sent  in  from  the 
field;  Mr.  I  line,  for  the  excellent  and  rapid  manner  in  which  tin-  reared 
and  collected  insects  were  mounted:  Mr.  Clifton,  for  assistance  along 
other  lines,  and  especially  Mr.  Schwarz,  who  devoted  much  timeout 
side  of  office  hour-  in  helping  me  t<>  make  tin1  preliminary  investigation 
and  classification  of  alcoholic  material  and  the  determination  of  the 
( Joleoptera. 

In  addition  to  the  ahove  I  should  mention  my  obligations  to  United 

States  Senator  McBride  for  letter-  of  introduction  t<»  persons  in  ( Oregon 
who  gave  me  valuable  information. 

Among  the  entomologists  and  other  members  of  the  -tail'  or  faculty 
of  the  several  universities  and  experiment  station-  visited  whose  hos- 
pitality and  interest  in  furthering  the  objects  of  the  journey  deserve 
special  mention  were  Dr.  Hilgard  and  Professors  Woodward  and 
Davy,  of  the  University  and  Experiment  Station  at  Berkeley,  Gal.; 
Professors  Cordley  and  Lake,  of  the  Agricultural  College  and  Experi- 
ment Station  at  Oorvallis, Oreg. ;  Professor  Kincaid,  of  tin-  Mate  Um- 
yersity  of  Washington;  Professor  Piper,  of  the  Agricultural  College 
of  Washington,  and  Professors  Aldrich  and  Henderson,  of  the  Univer- 
sity  of  Idaho. 

A.  D.  II. 
4 


CONTEXTS 


Page. 

Outline  of  trip,  and  localities  visited 7 

Summary  of  work  and  results 12 

Information  on  the  habits  of  Scolytids  made  the  prime  object 13 

Principal  Scolytid  enemies  of  forests  of  the  Northwest 13 

Destructive  Buprestid  enemies  of  Hemlock,  red  fir,  and  Noble  fir 17 

Forest-tree  defoliators 17 

Beneficial  insects  and  diseases 19 

General  observations  on  forest  trees  and  forest  conditions 19 

General  observations  on  some  forest  problems  of  the  Northwest 22 

Consideration  of  preventives  and  remedies 25 

Summary  and  recommendations 26 

5 


Digitized  by  the  Internet  Archive 

in  2012  with  funding  from 

University  of  Florida,  George  A.  Smathers  Libraries  with  support  from  LYRASIS  and  the  Sloan  Foundation 


http://archive.org/details/inaryreporOOunit 


PRELIMINARY  REPORT  ON  THE  INSECT  ENEMIES  OF 
FORESTS  IN  THE  NORTHWEST. 


OUTLINE    OF   TRIP.   AND    LOCALITIES    VISITED. 

I  left  Morgantown,  W.  Ya..  April  (J.  and  Washington,  L).  C.  April 
L2,  and,  going  by  the  southern  route  through  Texas.  New  Mexico, 

Arizona,  and  California,  arrived  in  San  Francisco  on  the  evening  of 
April  IT.  The  following  day  (April  18)  was  spent  in  visiting  the 
University  of  California,  at  Berkeley,  where  I  called  on  Professor 
TYoodworth,  entomologist,  and  Prof.  J.  B.  Davy,  botanist,  of  the 
Agricultural  Experiment  Station,  who  offered  every  facility  and  gave 
valuable  assistance  in  my  study  of  the  native  forest  trees  represented 
in  the  university  arboretum.  Here  I  collected  numerous  species  of 
Scoh^tids  from  the  pines  and  other  conifers. 

On  April  19  I  proceeded  to  Guerneville.  Cal.,  some  TO  miles  north 
of  San  Francisco,  to  investigate  the  insect  enemies  of  the  California 
redwood  {Sequoia  seniperwrms),  and,  in  addition  to  several  other  spe- 
cies of  insects  collected  from  the  bark  and  wood  of  this  tree,  I  found 
that  PMoeosiniix  cristatus  was  a  very  common  enemy. 

On  April  20  considerable  time  was  spent  in  Golden  Gate  Park,  San 
Francisco,  studying  the  indigenous  trees  of  the  Pacific  coast  repre- 
sented there,  and  in  collecting  specimens  of  insect  enemies  of  the  park 
trees.  I  also  called  on  Mr.  X.  Hoffman,  who  is  a  dealer  in  imported 
and  native  woods,  and  is  well  informed  on  the  timber  interests  of  the 
Pacific  coast,  and  obtained  front  him  some  valuable  information. 

I  left  San  Francisco  to  pursue  my  investigations  in  the  vicinity  of 
McCloud  and  Sisson,  Cal..  where  I  had  been  informed  some  timber 
was  dying,  and  arrived  at  the  former  place,  a  small  village  in  the 
heart  of  the  yellow  and  sugar  pine  forests,  on  the  southern  slopes  of 
Mount  Shasta.  April  21.  Among  the  more  important  observations 
made  here  was  the  discovery  of  a  bark-beetle  of  the  genus  Den- 
droctonus  killing  the  yellow  pine,  and  another  of  the  genus  Scolvtus 
doing  great  damage  to  living  fir  trees.  In  addition  to  this  a  large 
number  of  heretofore  unrecorded  facts  were  noted  regarding  the  insect 
enemies  of  the  spruce,  fir,  cedar,  pines,  etc.  The  owners  of  the  timber 
in  this  locality  expressed  themselves  as  much  interested  and  pleased 
that  these  subjects  were  being  investigated,  and  they  kindly  offered 


every  facility  for  prosecuting  the  work,  furnishing  livery,  tools, 
guides,  etc. 

April  22,  I  arrived  at  Grants  Pass,  Oreg.,and  investigated  the  con- 
dition of  the  forests  in  relation  to  insect  depredations  in  the  moun- 
tains north,  northeast,  and  southwest  of  the  city.  The  most  important 
feature  found  here  was  the  prevalence  of  the  same  species  of  Dendro- 

CtonUS  discoi  eivd  at   Mc(  loud,  and  many  hundred-  of   tree-  \\  hich  had 

evidentrj  died  from  it-  attack.  In  one  place  a  group  of  over  thirty 
trees  were  dying.  These  were  carefully  investigated.  The  living  and 
dying  bark  were  found  to  be  infested  with  different  stages  of  the 
Dendroctonus,  and  quite  conclusive  evidence  was  found  that  the 
death  of  these  trees  was  primarily  due  to  the  attack  of  this  bark- 
beetle.       In   another  section    it    wa-    found   that    the   same   Species   had 

attacked  the  sugar  pine.  Pmus  lambertiana,  which,  with  Pinusjxmder- 

iiv  among  the  most  valuable  timber  trees  of  the  Northwest.     The 

discovery  was  also  made  here  that  this  Dendroctonus  was  not  attracted 

to  felled  trees,  as  is  the  case  with  most  other  Scolytids,  but  is  attracted 

to.  and  freely  breeds  in.  tree-  that  have  been  girdled  by  the  settlers 
and  farmers  in  the  process  of  clearing  the  land:  and  that  these  trees 
form  nuclei  for  the  multiplication  and  spread  of  the  pest  to  the  healthy 
t  rees  in  adjoining  forests. 

Leaving  Grants  Pass  on  the  27th,  I  spent  a  few  hour-  profitably  col- 
lecting specimens  near  Albany  and  Corvallis,  arriving  at  the  latter 
place  in  the  evening.  In  accordance  with  instruction-  1  visited  the 
agricultural   college  and    experiment    station    here    on    the   I'l'th.   and 

called  on  the  entomologist,  Prof.  A.  B.  Cordley. 

The  next  day.  April  :;<>.  accompanied  by  Professor  Cordley.  I  pro- 
ceeded to  Newport,  Oreg.,  at  the  mouth  of  Yaquina  Bay.  where  I 
spent  the  day  investigating  the  insect  enemies  of  the  tree-  of  this  moat 
interesting  section.  Among  the  important  observations  made  here 
was  my  discovery  of  a  Scolytid  enemy  of  the  white  alder (Al/nw  f/><>in- 
bifoUa),  which  is  very  common  and  quite  injurious  to  this  tree.  Another 
species  of  Scolytid,  representing  an  undescribed  Hylesinus,  was  found 
t<>  he  common  in  the  hark  of  recently  felled  hemlock.  These  observa- 
tions had  the  added  interest  <>f  being  the  first  record  of  Scolytid  bark- 
beetles  infesting  alder  and  hemlock.     An  ondescribed  Dendroctonus 

Was  found  in  the  hark  of  Picea  dtchensis,  and  several  other  Scolytids. 

which  are  ondescribed,  were  found  in  this  spruce  and  in  Pvnvs  contorta. 
I  was  also  fortunate  in  finding  in  a  cone  of  the  last-named  tree  Mr. 
Schwarz's  rare  and  interesting  species,  Pitiyopkthorus  oofoiperda,  the 
occurrence  of  which  on  this  coast  is  most  remarkable.  Taking  it  all  in 
all,  this  locality  proved  to  he  one  of  especial  scientific  and  economic 
interest 

May  1.  we  returned  to  Corvallis.  and  the  following  day,  accompanied 
kv  Professor  Lake,  horticulturist  and  botanist  of  the  college  and  sta- 


9 

tion,  we  proceeded  into  the  Cascade  Range,  stopping  at  Detroit,  near 
the  terminus  of  the  railroad,  where  two  days  were  spent  in  profitable 
observations  of  the  forest  conditions  and  insect  enemies  of  the  cedars, 
firs,  spruces,  pines,  hemlock,  maple,  etc. 

May  4.  two  guides  were  secured  at  Berry,  Oreg.,and  we  entered  the 
Cascade  Forest  Reserve.  Here  I  made  some  important  observations 
regarding  a  trouble  which  had  caused  the  death  of  large  numbers  of 
noble  firs  (Abies  rvcMUs)  and  hemlock.  While  I  was  not  able  to 
secure  specimens  of  the  insects  which  doubtless  caused  the  death  of 
these  trees  (owing  to  the  fact  that  the  trees  had  been  dead  too  long),  I 
concluded  from  the  character  of  their  work  on  the  outer  sapwood  that 
it  must  be  a  Buprestid,  possibly  belonging  to  the  genus  Melanophila. 
Many  had  healed  over  before  the  trees  died,  thus  presenting  con- 
clusive evidence  that  they  were  attacked  while  living  and  probably 
while  in  healthy  condition. 

While  on  my  way  to  Portland,  May  5,  I  stopped  at  Salem  and  called 
on  Mr.  E.  C.  Giltner,  to  whom  I  had  a  letter  of  introduction  from 
United  States  Senator  McBride.  Mr.  Giltner  was  very  kind  in  giving 
information  and  in  introducing  me  to  persons  who  were  familiar  with 
the  forest  conditions  of  certain  sections  of  the  State. 

May  T,  I  proceeded  to  St.  Helen,  Oreg.  Here  investigation  was  made 
of  a  serious  trouble  affecting  the  hemlock  and  red  fir,  which  proved 
to  be  similar  to,  if  not  identical  with,  that  affecting  the  hemlock  and 
noble  fir  in  the  Cascade  Reserve,  near  Berry.  The  work  of  a 
Buprestid  larva  was  found  in  healthy,  dead,  and  dying  trees,  and  I 
was  fortunate  in  securing  a  few  larvse,  also  some  nice  specimens  of 
healed-over  galleries.  The  latter  presented  conclusive  evidence  that 
the  attack  had  been  made  on  healthy,  growing  trees.  It  seems  that 
the  trees  succumb  only  after  several  years  of  successive  attack  by  this 
insect.  The  extensive  cutting  of  timber  for  fuel  carried  on  here  does 
not  seem  to  answer  the  usual  purpose  of  attracting  the  insects  awa}T 
from  the  living  trees.  Therefore,  this  is  a  problem  of  considerable 
interest,  and,  under  more  favorable  conditions  for  stud}T,  should  receive 
attention,  in  order  to  determine  some  method  of  preventing  the  rav- 
ages, which  may  prove  to  be  even  more  extensive  than  at  present. 
In  the  evening  I  called  on  Mr.  W.  H.  Dolman,  with  a  letter  of 
introduction  from  Senator  McBride,  and  that  gentleman,  from  his 
experience  and  practical  knowledge,  was  able  to  give  me  A^aluable 
information  regarding  the  forest  conditions  in  that  section  of  the  State. 

Leaving  St.  Helen  May  8, 1  arrived  at  Astoria,  Oreg.,  the  next  morn- 
ing, and  made  observations  and  collections  in  this  most  interesting 
locality. 

May^  9,  I  proceeded  to  Seaside,  Oreg.,  where  I  learned  of  a  serious 
trouble  affecting  the  timber  some  14  miles  back  on  the  Coast  Range  in 
the  vicinity  of  Ahlers.     I  at  once  secured  a  guide  and  horses  and  pro- 


Ill 

ceeded  some  7  miles  thai  night  The  next  morning  we  followed  a  trail 
through  tin-  dense  and  magnificent  forest  here  to  Aiders,  where  the 
timber,  as  far  as  could  be  seen  in  all  directions,  was  dead.  The  I 
had  been  dead  eight  or  nine  years;  hence  it  was  not  possible  to  per- 
sonally investigate  the  cause  of  the  trouble.  I  was  particularly  fortu- 
nate, however,in  obtaining  from  the  postmaster,  Mr.  Herman  Aider-. 
a  most  interesting  account  of  the  beginning  and  ending  of  the  trouble 
as  observed  by  him  at  the  time.  It  -din- that  the  trees  were  defoli- 
ated, probably  bj  a  geometrid  larva,  in  L890  91,  and  that  nearly  all  of 
the  hemlock  and  Tideland  Bpruce  on  an  area  lying  hetwe.-n  460 and 
1,200  feet  above  -<•;!  level  in  the  southern  half  of  Clatsop  and  the 
northern  half  of  Tillamook  counties  died  as  a  direct  result  of  this 
defoliation. 

Returning  to  Seaside  May  LI,  I  did  some  collecting  there  from  Bcrub 
pine.  Tideland  spruce,  and  reel  fir,  securing  several  species  of  insects 
new  to  the  collection.  At  Billsboro,  Oreo-..  I  called  on  Congressman 
Tongue,  of  the  First  district  of  ( Oregon,  who  heartily  approved  of  the 
work  in  which  I  was  engaged  and  expressed  the  hope  that  good  results 
would  follow. 

May  L2th  proceeded  to  northern  Washington  to  continue  investiga- 
tions in  that  region,  stopping  one  day  at  Seattle,  and  arriving  at  Port 
Angeles  May  L5.  Here  two  day-  were  spent  in  active  work,  and  many 
additional  fact-  were  determined  and  valuable  material  added  to  the 
collection.  In  addition  to  many  of  the  same  set  of  enemies  of  the 
common  forest  trees  observed  at  other  points  visited,  I  found  here  a 
lepidopterous  Larva,  as  yet  undetermined,  which  was  quite  common. 
feeding  on  the  leaves  of  red  fir. 

Returning  from  Port  A.ngeles,  I  stopped  two  days  (May  1.7,18)  at 
Port  William-.  Wash.,  where  a  special  investigation  was  made  to 
determine  the  cause  of  the  death  of  a  large  number  of  white  fir  and 
red  fir  on  a  small  military  reserve  there.  It  was  found  that  the 
trees  were  being  attacked  by  the  same  Scolytus  a-  the  one  observed 
neai-  McCloud,  CaL,  and  also  by  a  new  Hylesinus.  The  red  fir  was 
infested  with  Dendroctonus  similis,  and  it  was  quite  evident  that  this 
species  was  the  cause  of  their  death.  Some  of  the  tree-  were  felled 
for  the  purpose  of  making  a  thorough  study  of  the  insects  inhabiting 
them.  Some  important  facts  were  learned,  and  a  large  -eric-  of  speci- 
mens of  the  insects  and  their  work  was  collected. 

Returning  to  Seattle  on  the  L9th,  1  -pent  the  next  day  with  Professor 
Kincaid.  entomologist  at  the  State  University,  and  several  hours  were 
employed  ;n  collecting  on  the  extensive  and  partly  fore-ted  university 
campus. 

Leaving  Seattle  May  20,  I  proceeded  to  eastern  Washington  and 
northern  Idaho,  where  nearly  two  week-  were  -pent  in  the  vicinity  of 
Spokane  and  Buckeye,  Wash.,  and  Sand  Point  and  Kootenai,  Idaho. 


11 

making  investigations.  Here  I  found  quite  different  conditions  pre- 
vailing from  those  observed  in  western  Washington  and  Oregon  in 
the  prevalence  of  quite  a  different  sel  of  foresl  trees,  notably  the 
lodge-pole  pine  (PinvA  murrayema),  the  mountain  white  pine  {Pmus 
monticola))  and  the  Western  larch  (La/rix  ocddentalii),  all  of  which 
yielded  a  large  amount  of  new  material  and  furnished  new  problems 
for  study. 

Among  the  more  important  observations  made  here  was  the  common 
occurrence  of  the  same  Dcndroctonus  enemy  of  the  yellow  pine 
observed  in  northern  California  and  southern  and  central  Oregon. 
Many  trees  were  found  in  the  vicinity  of  Buckeye,  Wash.,  which  were 
dying  or  had  died,  evidently  from  the  attack  of  this  insect,  since  in 
every  tree,  of  a  large  number  examined,  abundant  examples  of  the 
insect  and  its  work  were  found.  I  also  found  that  a  serious  trouble 
had  prevailed  among  the  white  pine  in  the  vicinity  of  Kootenai,  where 
a  large  amount  of  this  most  valuable  timber  had  died  within  the  past 
eight  or  ten  years.  Upon  investigation  I  found  quite  conclusive  evi- 
dence that  the  damage  had  been  caused  by  another  undescribed  Den- 
droctonus  allied  to  D.  frontalis,  but  much  larger  than  this  or  the  one 
found  killing  the  Western  }Tellow  pine. 

Dendroctonus  similis  was  found  quite  abundant  in  larch,  excavating 
galleries  and  depositing  eggs  in  living  bark  in  recently  felled  trees. 
Its  habits  and  the  common  occurrence  of  its  work  in  standing  dead 
trees  indicated  that  it  was  one  of  the  principal  enemies  of  this  kind  of 
timber. 

In  addition  to  the  above  observations  many  others  were  made  on  the 
enemies  of  the  pines,  spruces,  cedars,  larches,  birches,  poplars,  willows, 
etc. ,  and  a  large  series  of  valuable  specimens  was  added  to  the  collection. 

After  making  quite  a  thorough  investigation  of  the  conditions  found 
in  this  section  of  Washington  and  Idaho,  I  proceeded,  on  June  3,  to 
Pullman,  Wash.,  where  I  visited  the  Agricultural  College  and  Experi- 
ment Station  and  called  on  the  entomologist,  Professor  Piper. 

June  4  Professor  Piper  took  me  into  the  forest  at  the  base  of  Cedar 
Mountain,  Idaho,  where  a  few  hours  were  spent  in  successful  collection 
of  insect  enemies  of  the  spruce,  fir,  pine,  and  other  trees  in  this  region. 
Many  new  observations  were  made  here  and  much  new  material  col- 
lected. 

June  5  was  spent  with  Professor  Aldrich,  entomologist  of  the  Idaho 
University  and  Agricultural  Experiment  Station,  who  was  naturally 
much  interested  in  the  object  of  my  trip,  since  it  was  partly  through 
his  suggestion  that  this  work  was  undertaken. 

On  June  6  I  made  another  excursion  into  the  forests  of  Cedar  Moun- 
tain in  company  with  the  botanist  of  the  University  of  Idaho,  Pro- 
fessor Henderson,  and  three  students  from  the  botanical  and  entomo- 


•> 


logical  classes.  Among  the  additional  facte  obtained  on  this  excursion 
was  the  discovery  thai  the  Dendroctonus  enemy  of  the  yellow  pine 
attacks  trees  defoliated  by  the  pine  butterflj  (Neophobia  menapia), 
and  thai  it  is  quite  intimately  associated  with  the  destruction  of  a 
large  amount  of  timber  onlj  partly  defoliated  by  the  butterfly  larva. 
( )u  lng  to  the  earliness  of  the  season,  no  observations  could  be  made  <>n 
this  Insect  which  has  been  in  previous  years  so  enormously  abundant 
and  destructive  in  eastern  Washington  and  in  Idaho  and  Montana. 
Indeed,  it  was  ttardrj  necessary  that  I  should  do  so,  since  tin-  subject 
has  received  considerable  attention  at  the  hand-  of  Professor  Aldrich. 
Further  information,  however,  on  the  relations  of  Scolytids  to  the 
subsequent  death  of  trees  only  partly  defoliated  by  it  is  a  subject  of 
considerable  importance  which  I  believe  has  not  previously  been  taken 
into  consideration. 

Leaving  Moscow  on  the  7th  of  June  and  going  via  Pendleton,  <  >reg., 
and  Shoshone,  Idaho.  I  arrived  at  Hailev.  Idaho.  .June  !♦.  where  some 
successful  collecting  was  made  from  red  fir  logs  at  a  sawmill,  and 
some  valuable  information  was  obtained  from  Messrs.  Watt  and 
Peacock  regarding  the  forest  conditions  and  timber  interests  of  that 
section  of  Idaho.  Learning  of  nothing  else  of  especial  importance 
requiring  my  attention.  I  started  on  my  return  journey  to  Washington, 
D.  C.,  where  I  arrived  on   the   morning  of  June  17.  L899. 

The  total  distance  traveled  from  Washington,  D.  ('..  and  return  by 
rail,  boat,  wagon,  and  on  foot  was  about  9,000  miles;  the  time  occu- 
pied, sixty-sis  day-:  the  number  of  localities  visited,  twenty-six. 
The  number  of  specimens  collected  is  as  follow-: 

Bcolytidse,  mounted  (counted)  

Scolytidse,  in  alcohol  (counted)  2 

Miscellaneous,  principally  ( Soleoptera,  in  alcohol  (counted) 

Miscellaneous,  mounted  and  in  alcohol  (estimated) 

Specimens  of  work  oi  insects  (counted) 

Total 4.  363 

Separate  not.-  in  ooteb ok 700 

While  the  number  of  specimens  is  not  a-  large  a-  might  have  been 
secured  bv  general  collecting:,  the  manner  in  which  nearly  all  were 
collected  from  their  host  plants,  and  the  large  series  of  notes  on  their 
habit-,  make-  them  all  the  more  valuable 

SUMMAB7.    «>!'   WOBE    AND    RESULTS. 

The  above  outline  of  the  trip  will  indicate  the  character  and  amount 
of  work  done  and  the  success  attained  in  efforts  to  carry  out  instruc- 
tions. 

The  distance  traveled,  the  number  of  localities  visited,  and  the  lim- 
ited time  occupied  in  the  trip  from   Washington  and   return  left   but 


13 

little  time  for  actual  work  in  the  field.  Realizing  that  this  would  l»c 
the  case,  [  devoted  my  attention  to  the  investigation  of  a  iVw  leading 
features  which  promised  to  yield  the  host  results. 

INFORMATION  on  TI IK    HABITS   OF   SCOLYTIDS    MADE   THE    PRIME  OBJECT. 

Previous  to  this  trip  Little  had  been  published  regarding  the  host 
plants  and  habits  of  the  ScolyticUe  of  the  Northwest,  and  scarcely  any 
observations  had  been  made  on  the  relation  of  this  destructive  class  of 
insects  to  the  unhealthy  conditions  of  the  timber.  I  felt,  therefore, 
that  with  my  previous  experience  in  the  study  of  these  insects  in  the 
forests  of  West  Virginia,  it  was  my  first  duty  to  obtain  as  much  infor- 
mation as  possible  regarding  the  habits  of  those  found  in  the  localities 
visited,  and  I  spared  no  pains  or  labor  to  accomplish  this  end.  As  a 
result  of  this  effort  specimens  of  some  sixty  species  of  Scolytids,1  rep- 
resenting some  twenty  genera,  were  secured.  This  includes  nearly  all 
of  the  species  heretofore  known  from  northern  California,  Oregon, 
Washington,  and  Idaho.  It  also  includes  a  large  number  heretofore 
unknown  from  this  region,  with  representatives  of  two  or  three  new 
genera.  The  host  plants  and  some  features  of  the  habits  and  life  his- 
tory of  every  species  were  determined.  A  large  series  of  biological 
material  of  both  the  undescribed  and  described  species  was  also  col- 
lected. 

PRINCIPAL  SCOLYTID  ENEMIES  OF  THE  FORESTS  OF  THE  NORTHWEST. 

The  genus  Dendroctomis. — This  genus,  which  has  been  found  to  con- 
tain some  of  the  most  destructive  enemies  of  the  conifers  of  the  East, 
was  found  to  be  represented  in  the  Northwest  by  three  described  and 
two  or  three  undescribed  species.  They  were  found  here,  as  in  the 
East,  to  be  the  principal  enemies  of  pine,  spruce,  and  larch;  and  from 
what  was  observed  of  their  habits  it  is  plain  that  under  favorable  con- 
ditions most,  if  not  all,  of  them  are  capable  of  attacking  and  killing 
healthy  timber. 

One  species  which  I  have  provisionally  identified  as  Dmdrocton  us 
hrevicomis  Lee.2  was  found  to  be  a  most  destructive  enemy  of  the 

1  This  is  the  number  of  the  species  determined  by  Mr.  Schwarz  and  myself  in  a 
preliminary  study  of  the  entomological  material.  Subsequent  identification  of  the 
mounted  specimens  may  show  that  there  are  a  few  more  or  a  few  less  species  and 
genera. 

2  Heretofore  this  species  had  not  been  recognized  since  it  was  first  described  by 
LeConte.  Dr.  Dietz,  in  his  notes  on  species  of  Dendroctonus  of  boreal  America,  states 
that  he  does  not  recognize  any  difference  in  typical  specimens  of  D.  frontalis  Zimm. 
and  D.  hrevicomis,  Lee,  and  consequently  concludes  that  they  are  identical.  The 
examples  I  found  are  undoubtedly  distinct  from  D.  frontalis,  although  very  closely 
allied  to  this  species  in  specific  characters  and  habits.  It  agrees  so  closely  with 
Le  Conte's  description  of  D.  hrevicomis,  however,  that  I  think  it  must  be  recognized 
as  such  until  a  comparison  with  the  type  proves  the  contrary. 


14 

yellow  pine  i/V////>  ponderosa)  in  northern  California,  southern  and 
eastern  Oregon,  northeastern  Washington,  and  western  [daho.  A  Large 
amount  of  some  of  the  finest  timber  in  all  of  these  localities  had  died 
within  the  past  seven  or  eight  years,  evidently  as  a  direct  result  of 
attack-  i>\  tin-  barb  beetle.  It  was  also  found  to  attack  and  prevent 
the  recovery  of  tree-  injured  by  defoliating  insects  and  other  causes. 
It-  habits  and  the  character  of  it-  galleries  appear  to  be  identical  with 

those  of   1  >>  ml  i-<><-f"inis  fr<,iif<ilis.   which  i-   noted   for    it-  dc-t  ruction    of 

\  a-t  quantities  of  pine  and  spruce  timber  in  W'e-t  Virginia  and  adjoin- 
ing State-  between  L890  and  L893.  It  is  killing  the  Western  yellow 
pine,  just  as  D.  frontalis  commenced  to  kill  the  Eastern  yellow  pine 
(/V////.S ■< chvnata)  before  it  spread  to  all  tin-  other  pine-  and  spruce. 
Therefore,  just  as  D.  frontalis  has  proven  to  be  the  most  destructive 
enemy  of  Eastern  conifers,  the  Western  representative  of  this  species 
will  doubtless  prove  to  be,  under  similarly  favorable  condition-,  equally 
as  destructive  to  the  Western  forests  in  which  the  conif ers  predominate. 

Among  the  nio-t  important  features  observed  regarding  the  habits  <d 
this  hectic  was  the  fact  that  it  is  attracted  to  tree-  girdled  i>\  settlers 
and  fanner-  in  the  process  of  clearing  land,  and  that  in  the  hark  of 
such  trees  it  breeds  and  multiplies  in  sufficient  numbers  to  enable  it  to 
attack  and  kill  the  timber  in  adjoining  healthy  forests.  Indeed,  my 
observation  lead-  me  to  conclude  that  a  considerable  number  of  girdled 
pine  tree-  may  easily  form  a  nucleus  for  a  destructive  invasion  by  it. 

A  Dendroctonus  allied  to  the  one  just  mentioned,  hut  evidently  unde- 
scribed,  was  found  to  be  a  special  and  dangerous  enemy  of  the  sugar 
pine  ( Pmvs  lambertiana)  and  the  mountain  white  pine  (Pinus  monti- 
oola\  especially  of  the  latter.  It  was  frequently  met  with  in  the 
vicinity  of  Grants  Pass.  Oreo-.,  in  sugar  pine,  and  was  found  abundant 
in  the  hark  of  dying  and  dead  standing  and  felled  white-pine  tree-  in 
the  vicinity  of  Sand  Point  and  Kootenai.  Idaho,  where  a  large  amount 
of  timber  had  died,  evidently  a-  a  result  of  it-  attack.  This  i-  the 
same  hectic  a-  the  one  -cut  to  the  Division  of  Entomology  by  Mr. 
Aye]--  from  Columbia  Fall-.  Mont.,  and  subsequently  sent  to  me.  with 
other  Dendroctonus  material,  for  study.  It  is  undoubtedly  capable  of 
attacking  and  killing  great  quantities  of  white  and  sugar  pine,  hut  may 
possibly  he  prevented  from  doing  so  in  the  future,  in  all  regions  where 
extensive  timber  cutting  is  carried  on.  by  it-  being  attracted  to  the 

-tumps,  loo-,  and  top.-  of  trees  felled  for  lumber  and  fuel. 

Another  specie-,  at  present  recognized  a-  Dendroctonus  terebrans, 
wa-  commonly  met  with  in  the  hark  of  living,  dying,  and  dead  stand- 
ing trees  and  the  stumps  of  recently  felled  Pinus  ponderosa,  P,  lam- 
bertiana,  l\  monticola,  l\  murrayana,  P.  contorta,  and  I\  radiata,  in 
all  <>f  the  localities  where  these  species  of  pine  grow.  It  was  found 
to  l't>  quite  a  common  enemy  of   the   Monterey  pine  on  the  university 

campus  at  Berkeley,  CaL,and  I  wa-  informed  by  Professor  Davy  that 


15 

the  unhealthy  conditio!!  of  this  pine  in  iis  native  home  (Monterey 
County,  Cal.)  was  probably  due  to  the  attack  of  this  or  of  a  closely 
allied  bark  beetle.  The  fact  that  it  was  not  found  in  spruce,  fir,  or 
larch  indicates  tlmt  in  the  Northwest,  as  iii  the  East,  this  large  repre 
sentative  of  the  genus  almost  exclusively  infests  the  pine.  Its  habit  of 
attacking  trees  at  the  base  is  the  same  as  in  the  East,  as  are  also  the 
social  habits  of  the  larvae. 

The  information  I  was  able  to  gather  of  the  habits  and  different 
stages  of  the  Western  representative's  of  D. terebrans,  of  which  nothing 
had  been  recorded,  will  aid  greatly  in  arriving  at  definite  conclusions 
regarding  the  identity  of  numerous  doubtful  forms  collected  on  this 
trip,  and  those  among  the  large  series  of  material  in  the  national  col- 
lection. 

Another  Dendroctonus,  referred  to  in  my  notes  as  "Dendroctonus  sp., 
near  rafipennis^  proved  upon  eomparison  with  identified  specimens  in 
m v  collection  to  be  the  same  as  examples  labeled  D.  similis. l  It  appears 
that  nothing  has  heretofore  been  recorded  regarding  the  host  trees  or 
habits  of  this  insect,  yet  I  found  it  to  be  one  of  the  commonest  bark 
beetles  of  the  region  traversed,  and  a  special  enemy  of  the  red  fir 
(Pseudotsuga  taxifolia).  It  was  especially  abundant  wherever  this 
tree  was  being  cut  for  fuel  or  lumber.  Partially  developed  broods 
were  in  the  bark  of  trees  felled  the  previous  year,  and  some  had  emerged 
and  were  entering  the  bark  of  logs  and  stumps  of  recently  felled  ones, 
in  the  living  bark  of  which  they  were  excavating  galleries  and  depos- 
iting eggs.  On  a  small  military  reservation  at  Port  Williams,  Wash., 
I  found  it  associated  with  the  death  of  large  numbers  of  red  fir, 
and  in  eastern  Washington  and  northern  Idaho  it  was  found  to  be  quite 
as  common  an  enemy  of  the  Western  larch  {Larix  occidentalis)  as  of 
the  red  fir.  The  fact  that  it  was  found  so  common  in  these  two  kinds 
of  trees,  and  not  in  Picea  or  Abies,  suggests  that  there  is  possibly  a 
closer  affinity  between  Pseudotsuga  and  Larix  than  has  heretofore 
been  recognized  by  botanists. 

An  undescribed  Dendroctonus,  near  D.  rufijpennis,  was  found  in  the 
bark  of  Tideland  spruce  near  Newport,  Oreg.  This  beetle  is  repre- 
sented in  the  national  collection  by  a  few  large,  black  examples  from 
Queen  Charlotte  Island,  and  in  my  collection  by  a  large  series  recently 
sent  to  me  for  identification  from  the  same  island  by  the  Reverend 
Keen.  This  is  very  likely  a  special  enemy  of  the  Tideland  spruce. 
and,  judging  from  the  habits  of  other  species  of  the  genus,  will  doubt- 
less prove  at  times  quite  injurious  or  destructive. 

The  genus  Scolytns. — This  genus,  which  is  represented  in  the  East  by 
three  common  species  which  depredate  on  deciduous  trees  (viz,  Scolytns 
rugulosus  on  fruit  trees,  S.  quadrispinosus  on  hickory,  and  S.  muticus 

1  This  may,  after  all,  prove  to  be  D.  obesus  Mann.,  which  LeConte  believed  to  be 
synonymous  with  D.  rufipennis.     (Rhynchophora  of  North  America,  1876,  p.  385.) 


16 

on  hackberrj  >.  is  represented  in  the  West  bj  Beveral  Bpeeies  which 
infest  conifers.  The  genus  is  of  especial  interest  on  account  of  the 
destructive  powers  of  Borne  of  it-  representatives,  which  are  capable 
of  attacking  and  Living  in  the  bark  of  healthy  trees.  One  or  more 
unrecognized  Bpeeies  allied  to  8,  prweep*  were  found  to  be  primarily 
destructive  to  the  wood  of  li\  Lng  white  fir  trees  in  all  of  the  Localities 
visited.  The  beetles  attack  the  bark  of  healthy,  rigorous  trees  and 
excavate  their  primary,  <>!■  egg-galleries  transversely  through  the  inner 

hark  and  through  the  outer  surface  of  the  wood.      When  the  attack  is 

not  sufficient  to  kill  the  trees,  these  wound-  heal  over,  but  in  the  mean- 
time a  decay  often  sets  in  at  these  injured  places,  which  extends  through 
the  heart  wood  and  for  Beveral  feet  above  and  below  the  wound,  thus 
rendering  the  wood  worthless  for  Lumber,  and  often  for  fuel.    That 

these  trees  were  in  a  vigorous,  growing  condition  when  attacked  was 
proven  by  the  fact  that  in  many  instances  a  normal  growth  of  wood 
and  twigs  had  formed  the  year  the  attack  was  made,  and  when  the 
injury  was  not  sufficient  to  weaken  the  vitality  of  the  tree  a  normal 
growth  was  made  the  next  and  succeeding  years  until  the  wounds  were 
healed.  At  Port  Williams,  Wash.,  many  tree-  were  dying,  all  of  which 
were  infested  with  Larvae  and  pupae  of  one  or  more'  of  these  Scolytus 
enemies,  and  it  was  quite  evident  that  they  had  been  the  primary  cause 
of  the  trouble. 

Another  species,  at  present  recognized  as  -s'.  imispmMUS,  was  found 
to  be  a  very  common  enemy  of  red  fir  along  the  coast,  and  of  the  red  fir 
and  Western  larch  in  Idaho  and  eastern  Washington.  No  evidence  WBjB 
found,  however,  that  this  species  had  caused  the  death  of  any  of  the 
trees. 

Th>  genus  Tarruicw. — This  genus  is  represented  in  the  collection  by 
some  ten  species,  four  of  which  appear  to  he  new.  While  I  found 
some  evidence  to  indicate  that  a  species  recognized  as  Tomicus  pi/ni 
was  the  primary  cause  of  the  death  of  numerous  example-  ..f  the  Lodge- 
pole  pine  in  the  vicinity  of  Spokane  and  of  yellow  pine  near  MOSCOW, 
Idaho,  the  other  species  appeared  to  occur  only  a-  secondary  enemies 
or  a-  allies  of  the  more  affffressive  Dendroctonus. 

( >th<  r  Soohftids.  Among  the  other  numerous  species  of  Scolytids 
collected,  none  were  recognized  as  specially  destructive  enemi 
trees,  except  LeConte's  Hylesinvs  aspericollis,  which  is  nota  Hylesinus, 
hut  appears  to  represent  an  undescribed  genus,  characterized  by  a 
seven-jointed  antenna!  runicle.  This  I  found  infesting  the  Living  bark  of 
white  aldei-  (Alnus  rhwribifolAat),  with  evidence  that  it  not  only  hastens 
the  death  of  injured  tree-,  hut  that  it  may  he  the  primary  cause  of  the 
death  of  healthy  one-. 

Examples  of  larvae  and  pupse,  with  a  few  dead  adult-,  of  an  unde- 
scribed Hylesinus  were  found  quite  abundant  in  the  bark  of  a  felled 

hemlock  at    Newport.  Oreg.      This  and   the  one  found   in  alder  are  of 


17 

special  interest  from  the  fact  that  there  appears  to  be  no  previous 
record  of  a  Scolytid  bark-beetle  infesting  either  Ainus  or  Tsuga. 

Another  Scolytid,  which  does  not  seem  to  be  referable  to  any  known 
genus,  was  found  in  the  thin  hark  of  young  d\  ing  sugar  pine  trees  in 
the  vicinity  of  Grants  Pass,  Oreg.;  also  in  other  pines  and  jn  the 
red  fir. 

The  numerous  other  Scolytids  represented  in  the  collection  made  on 
this  trip  can  not  be  mentioned  in  this  preliminary  report,  but  will  form 
the  subject  of  several  pages  of  original  matter  in  my  final  report  on  the 
results  of  this  investigation. 

DESTRUCTIVE     BUPRESTID     ENEMIES     OF     HEMLOCK,    RED   FIR,    AND 

NOBLE   FIR. 

The  evidence  found  in  living,  d}Ting,  and  dead  noble  fir  and  hemlock 
in  the  Cascade  Forest  Reserve,  at  Berry,  Oreg.,  and  in  hemlock  and 
red  fir  along  the  Columbia  River,  in  the  vicinity  of  St.  Helen,  indicated 
that  much  loss  of  valuable  timber  had  been  due  to  the  work  of 
Buprestid  larvse  in  the  living  bark  of  these  trees.  The  conditions 
at  the  time  were  not  favorable  for  a  study  of  this  class  of  enemies  or 
for  a  special  investigation  of  the  damage  which  seemed  to  be  due  to 
their  attacks.  It  is,  however,  a  subject  of  special  importance,  which 
will  demand  considerable  attention  in  the  future.  Specimens  of  larvae 
collected  from  the  bark  of  living  trees  were  provisionally  identified 
by  Mr.  Schwarz  as  belonging  to  the  genus  Melonophila,  probably  M. 
drummondi,  which  is  closely  allied  to  M.fulvoguttata,  a  destructive 
enemy  of  the  hemlock  in  West  Virginia!  An  undetermined  Ceram- 
bycid  bark  borer  was  found  associated  with  the  Buprestid  larvae  in 
hemlock  and  red  fir,  but  the  evidence  pointed  to  the  Buprestid  as 
having  made  the  first  attack. 

FOREST   TREE   DEFOLIATORS. 

While  I  did  not  have  an  opportunity,  owing  to  the  earliness  of  the 
season,  to  investigate  the  insects  which  are  injurious  and  destructive 
to  the  foliage  of  forest  trees,  I  found  abundant  evidence  of  this  class 
of  depredators,  especially  in  the  work  of  the  pine  butterfly  on  the 
yellow  pine  of  eastern  Washington  and  western  Idaho,  and  the 
Geometrid  of  Clatsop  County,  Oreg. ,  on  Tideland  spruce  and  hemlock. 

The  work  of  the  pine  butterfly  has  been  previously  recorded  by 
Mr.  Stretch,  in  Papillio  (Vol.  II,  pp.  103-110),  and  subsequently 
copied  in  the  Fifth  Report  of  the  United  States  Entomological  Com- 
mission (pp.  762-767).  The  subject  has  also  received  special  attention 
within  recent  years  at  the  hands  of  Professor  Aldrich,  of  the  Idaho 
station ;  therefore  the  only  observation  made  by  the  writer  on  this  trip 
which  it  seems  proper  to  mention  in  this  connection  is  that  relating  to 
8602— No.  21 2 


18 

Dendroctonus,  Tomicus,  and  other  Scolytids  attacking  the  defoliated 
and  partly  defoliated  trees.  M\  observations  led  me  to  conclude  thai 
were  it  n<>t  for  the  secondary  attack  of  the  Scolytids  many  <>t'  these 
trees  would  have  recovered  from  the  injuries  by  the  butterfly  larvae. 
[ndeecL  ii  seems  to  me  that  this  association  of  bark  beetles  with  defo- 
liating  caterpillars  in  causing  the  death  of  trees  is  an  important  feature 
to  be  taken  into  consideration  In  an)  study  of  troubles  of  this  character. 

The  \\<>rk  of  the  supposed  geometrid  larva,  found  near  Ahlers, 
Oreg.,  has  not,  I  believe,  been  previously  recorded,  and.  while  I  did 
not  have  an  opportunity  to  see  specimens  of  this  insect,  which  has  not 
attracted  attention  since  the  summer  and  fall  of  L890,  I  obtained  some 
valuable  information  from  Mr.  Ahlers  regarding  the  character  of  the 
invasion,  the  insect,  and  the  extent  of  its  depredation-. 

Mr.  Ahlers,  postmaster  at  Ahlers,  took  a  course  in  entomology  at 
Wernififerode  am  liar/.  Province  of  Saxonv.  Hence,  his  observations 
are  of  especial  interest.     Mr.  Ahlers  said: 

The  worms  commenced  t"  attract  a  little  attention  here  in  1889.  \  few  moths 
seen  in  the  fall  of  the  saine  year.  In  July,  1890,  the  worms  appeared  ii. 
numbers,  the  first  on  tin-  hemlock,  feeding  on  the  base  of  tin-  leaves  and  cutting 
them  off.  When  standing  beneath  tin-  trees  tin-  droppings  from  tin-  insects  and  the 
falling  leaves  sounded  like  rain.  When  all  of  tin-  leaves  were  eaten  from  the  trees 
the  worms  would  let  themselves  down  by  means  of  webs,  and,  if  they  were  not  full 
grown,  would  feed  on  tin-  leaves  of  all  kinds  of  shrubs  and  trees,  except  tin-  Douglas 
spruce  and  cedar.  The  worms  were  observed  during  July  and  August,  and  disap- 
peared  in  the  Latter  month,  probably  going  into  the  ground  to  pupate.  In  October 
the  moths  began  to  come  <>ut.  They  w ere  grayish  white  with  dark  marking  on  the 
wings.  The  wings  spread  aboul  Li  inches.  The  moths  would  appear  on  the  wing 
about  :;  o'clock  in  the  afternoon  in  enormous  Bwarms  around  the  tops  of  tin-  trees, 
resembling  a  white  cloud.  They  continued  to  fly  for  about  three  weeks,  at  the  end 
of  which  time  the  ground  was  covered  with  the  .lead  insects,  and  the  .-mall  streams 
were  tilled  with  them,  iii  Borne  places  forming  dams.  The  next  year.  1891,  they 
attacked  the  sitka  Bpruce  and  defoliated  the  trees,  which  died  the  following  fall  or 
winter.  *  *  *  When  the  worms  were  coming  down  from  the  trees  the  webs 
made  the  trees  l"«'k  a-  if  they  were  covered  with  a  grayish  veil.  The  worm-  were 
about  i\  inches  long,   the  si<  -n  green,  with  darker  gray  zigzag  markings 

on  the  back.  When  traveling  they  measured  their  way.  This  trouble  extended 
over  parts  of  Clatsop  and  Tillamook  counties,  killing  all  the  hemlock  and  sitka 
Bpruce  in  a  bell  between  an  elevation  of  about  450  and  1,200  feet  above  tide.  The 
Douglas  spruce  and  red  cedar  were  not  injured. 

At  the  time  of  my  visit  much  of  the  area  covered  by  dead  timber 
had  been  frequently  burned  over  by  forest  tire-,  bo  that  in  some  places 
nearly  all  of  the  dead  timber  had  disappeared,  hut  in  other  places, 
where  the  condition-  had  not  been  bo  favorable  for  the  spread  of  the 
lire,  the  dead,  barkless  trunks  of  the  trees  were  Mill  standing,  the  tops 
broken  and  the  branches  fallen,  the  scene  presenting  at  once  a  most 
impressive  example  of  the  destructive  powersof  an  insect  enemy  of 
forests  and  of  subsequent  devastation  by  forest  fires. 

When  it  i->  considered  that  some  of  the  spruce  which  grow  here  are 
L0  to  13  feet   in  diameter.  300  feet  tall,  and  will  yield  more  Lumber 


19 

than  manv  an  acre  of  timber  in  the  Eastern  States,  one  can  have  some 

conception  of  the  vast  amount  of  timber  which  had  been  destroyed. 

While  the  caterpillars  which  were  primarily  to  blame  for  this  desl  rue 
tion  have  not  attracted  attention  within  recenl  years,  they  will  doubtless 
make  their  appearance   again  in   destructive   numbers  and   attack  the 
remaining  timber,  which  is  becoming  each  year  more  accessible  to 
lumbering  operations,  and  hence  rapidly  increasing  in  value. 

BENEFICIAL    [NSEOTS    \M>    DISEASES. 

A  large  series  of  predaceous  and  parasitic  insect  enemies  of  the 
principal  destructive  species  was  collected,  and  many  features  regard- 
ing their  occurrence,  distribution,  and  habits  noted.  The  predaceoie- 
enemies  of  Scolytids  were  quite  common  in  nearly  all  of  the  localities 
visited,  but  the  Chaleidid,  Braconid,  and  Ichneumonid  parasites  of 
Scolytids  and  other  bark  and  wood-infesting  insects  were  rare  as  com- 
pared with  the  same  class  of  insects  in  the  East. 

Numerous  examples  of  diseases  of  both  injurious  and  beneficial 
insects  were  found,  and  many  insects  had  died  from  their  effects.  It 
was  not  possible,  however,  with  the  limited  time  at  my  disposal  to 
determine  the  exact  relation  of  these  factors  to  the  injuries  caused  by 
the  principal  enemies. 

GENERAL  OBSERVATIONS  ON  FOREST  TREES  AND  FOREST  CONDITIONS. 

Forest  tree*  recognized  and  studied. — Some  22  species  of  conifers  and 
14  of  deciduous  trees  were  recognized  on  this  trip  and  their  insect 
enemies  studied,  the  following  of  which  deserve  special  mention  on 
account  of  their  common  occurrence  and  commercial  importance. 

COMMON   NAMES.  BOTANICAL  NAMES. 

Kedwood Sequoia  sempervin  us. 

Western  yellow  pine Pinus  p<>n<< 

Sugar  pine Pinus  lambertiana. 

Silver  pine  (Western  white  pine) Pinus  monticola. 

Red  fir  (Douglas  spruce) Pseudotsuga  taxifolia. 

Tideland  spruce Picea  sitchensis. 

Red  cedar Thuja  plicaia. 

Western  hemlock . Tsuga  heterophytta. 

Lowland  fir Abies  grandis. 

Noble  fir  ("  larch  ")  Abies  nobilis. 

Western  larch Larix  occidentalis. 

Each  of  the  timber  trees  named  in  this  list  was  found  to  have  one  or 
more  insect  enemies.  My  observations  on  these  trees  and  the  relation 
of  their  enemies  to  the  general  condition  of  the  timber  may  be  briefly 
summarized  as  follows: 

The  redwood. — This  appears  to  be  an  exceedingly  hardy  tree,  and  s< 
far  as  I  observed  in  the  short  time  spent  in  the  forests  of  this  species  in 
the  vicinity  of  Guerneville,  Cal.,  is  in  a  healthy  condition.     It  has. 


20 

however,  in   Phlceosit  status  an  enemy  which,   under  especially 

!';i\  orable  conditions,  might  prove  quite  destructive  to  standing  timber. 
At  present  this  insect  is  attracted  t<>  the  bark  of  felled  trees  in  which 
it  breeds  in  great  numbers.  A  Cerambycid  bark  borer,  CalUdium 
janthinum,  was  also  found  under  the  bark  of  a  felled  tree,  and  may 
be  a  common  enemj . 

'/'//,  Western  yellowpme.  This  is  widely  distributed  through  north- 
ern California,  Oregon,  Washington,  Idaho,  and  many  other  places 
wherevei  the  soil  and  climatic  conditions  are  favorable  t<»  it-  growth. 
Indeed,  it  is  one  of  the  commonest  and  most  valuable  timber  trees  of 
the  region.  From  the  evidence  found  it  has  probably  a  greater  num- 
ber of  insect  enemies  than  any  of  the  other  trees  mentioned,  and  at 
present  is  suffering  far  more  from  then-  ravages.  It  has  in  Dendroc- 
tn,,u.s  brevicomis  a  most  pernicious  enemy,  which  penetrates,  and 
excavates  winding  galleries  through,  the  living  hark  of  the  finest 
trees,  thus  speedily  causing  their  death.  Very  many  trees  have  died 
and  are  dying  from  this  cause,  and  the  dead  ones  are  contributing  to 
the  spread  of  forest  fires.  It-  next  greatest  enemy  is  the  pine  but- 
terfly, which  has.  from  time  to  time,  defoliated  and  caused  the  death 
of  much  of  the  best   yellow-pine  timber  in  eastern  Washington  and  in 

Idaho. 

'There  are  many  secondary  enemies  of  greater  or  lesser  importance 
among  the  Scolytid  genera  Pityophthorus,  Pityogenes,  Xyloterus, 
Tomicus,  Hylastes,  and  Hylurgops,  which  contribute  to  the  death  of 
trees  primarily  injured  by  defoliating  and  other  insects,  fire,  and  other 
causes.  Numerous  Buprestid  and  Cerambycid  enemies  of  the  wood 
and  bark  contribute  to  the  unhealthy  condition  of  the  timber  and  the 
destruction  of  the  wood.  A  lepidopterous  larva  infests  the  terminal 
twig  of  young  trees  near  Moscow,  Idaho,  and  one  or  more  Curculionid 
beetles  breed  in  the  hark  at  the  base  of  young  and  old  tr< 

The suga/r pine.-  While  this,  one  of  the  most  valuable  timber  trees 
of  California  and  southern  Oregon,  is  in  a  more  healthy  condition 
than  the  yellow  pine,  it  has  a  dangerous  enemy  in  an  Undescribed 
Dendroctonus  as  well  as  in  the  destructive  enemy  of  the  Latter.  It 
has  also  a  host  of  other  enemies  which  infest  the  twigs,  bark,  wood. 
and  roots. 

lln  sil '  r,  /•.  or  western  white  pine.—  This  is  a  very  common  and  m<>-t 
valuable  tree  in  eastern  Washington  and  in  Idaho,  and  has  a  special 
enemy  in  the  same  undescribed  Dendroctonus  thai  infests  the  sugar 
pine.  A  vast  amount  of  dead  timber  was  found  in  groups  and  -eat 
tered  through  the  forests  in  the  vicinity  of  Kootenai  and  Sandpoint, 
Idaho,  which  showed  <_:'<><>d  evidence,  in  the  great  abundance  of  gal- 
leries of  this  insect  in  the  bark,  that  they  had  been  killed  by  it.  A 
Tomicus,  closely  allied  to  oonfasvs^  was  also  found  to  he  a  verj  com- 
mon enemy,  entering  the  living  bark  ^^.   recently  felled  trees;  a-  was 


21 

als<»  a  Monohammus  larva,  which  was  found  mining  in,  and  destructive 
to,  the  wood  of  standing  and  felled  trees. 

Tfu  red  fir.  This  common  and  hardj  timber  tree  of  the  North- 
west,   is   of  especial    value   both   for  its   lumber  and    fuel   product. 

While  it   is  generally  in  a  healthy  condition,  many  dead  and  dying 
©  .  .  .— 

trees  were  found  in  all  the  sections  visited,  and  in  some  places 
sufficient  evidence  was  found  to  show  that  it  had  dangerous  ene 
niies  in  certain  Buprestid  and  Cerambycid  bark  borers,  which  are 
capable  of  living  in  the  healthy  hark  of  growing  trees.  It  has  also  a 
special  enemy  in  Dendroctonus  similis^  which  is  everywhere  common 
in  the  bark  of  dead  and  dying  standing  trees  and  in  the  dead  and  living 
hark  of  logs  and  stumps  of  felled  ones.  The  evidence  found  in  the 
dying  trees  on  the  military  reservation  at  Port  Williams  indicates  that 
this  bark  beetle  may,  under  favorable  conditions,  be  the  primary  cause 
of  the  death  of  the  trees.  Scolytus  unispmosm  is  also  a  very  common 
enemy,  infesting  the  hark  on  the  main  stem  of  small  trees,  and  on  the 
branches  of  larger  ones,  which  have  been  previously  injured  or  felled. 
A  lepidopterous  larva  was  found  feeding  on  the  foliage  near  Port 
Angeles,  and  its  common  occurrence  and  habits  of  feeding  indicate  that 
it  might  easily  become  quite  destructive  to  the  foliage. 

The  Tideland  spruce. — This  is  a  magnificent  tree,  found  in  great 
forests  along  the  coast  in  Oregon  and  Washington.  It  is  attacked  by 
several  pernicious  enemies,  the  principal  of  which  is  the  undetermined 
Geometrid,  mentioned  on  another  page,  which  has  destroyed  immense 
quantities  of  timber  and  will  doubtless  be  a  menace  to  timber  interests 
here  in  the  future.  The  undescribed  Dendroctonu*  found  in  the  bark 
and  trees  of  logs  at  Newport,  Oreg.,  is  a  special  enemy,  as  are  also 
Dvyocadex  affaber,  Ilylurgops  rugvpervnfa,  Xylotevus  bivittatus,  and 
some  other  bark  beetles  which  were  found  mining  in  the  partly  living 
bark  or  wood  near  Ahlers,  Oreg. 

Red  cedar. — This  is  a  common  tree  throughout  Oregon  and  Wash- 
ington, and  is  of  especial  value  for  shingles,  telegraph  poles,  and 
lumber.  Its  principal  enemies  are  one  or  more  species  of  Phlceo- 
sinus  and  the  Cerambycid,  Callidvwm  jemtkinum,  wThich  infests  the 
living  bark  of  recently  felled  trees  and  those  injured  by  tire  or  other 
causes.  The  heartwood  of  living  trees  is  also  seriously  injured  by 
ants,  which  extend  the  damage  started  by  Cerambycid  heartwood 
borers,  and  a  fungous  disease.  Numerous  dead  trees  were  observed  in 
all  sections  of  the  forest,  mam^  of  which  had  evidently  died  from 
injuries  by  one  or  more  of  these  enemies. 

The  hemlock. — This  is  also  a  common  hardy  tree.  It  is  attacked  by 
the  same  destructive  bark  borers  as  those  mentioned  under  red  fir  as 
well  as  by  the  Geometrid  mentioned  under  Tideland  spruce.  In  addi- 
tion to  these  it  has  an  undescribed  Scolytid  enemy  which  infests  the 
bark.     Many  dead  trees  were  found  in  the  Cascade  Reserve  and  both 


I  tig  and  dead  ones  in  the  forests  near  St.  Helen,  all  of  which  showed 
evidence  of  ha\  ing  b  <n  killed  or  injured  by  a  Buprestid  larva,  while 
the  great  numbers  of  dead  hemlock  in  Clatsop  County,  Oreg.,  were 
sufficient  evidence  of  the  destructive  powers  of  the  Geometric! 

77,,  white  or  grand  fir.  This  Is  a  very  common  tree,  which  would 
be  of  special  value  for  the  manufacture  of  pulp  but  for  serious  injuries 
i>\  one  or  more  species  of  Scolytus  and  Rylesinus,  which  infest  the 
living  tree-,  causing  a  decayed  condition  of  the  wood  of  some  and 
the  death  of  many  others,  so  that  the  fir  is  often  In  an  unhealthy 
condition  and  the  dead  and  decaying  trees  contribute  to  destructive 
forest  fires.  It  also  has  a  number  of  other  Scolytid,  Buprestid,  and 
Cerambycid  enemies  which  infest  the  wood  and  bark.  The  same 
caterpillar  that  was  found  attacking  the  foliage  of  the  red  fir  was  also 
found  feeding  on  the  leaves  of  this  fir. 

Th,    nobli  fir.-     This    is,    a-^    its   name   indicate-,  a   most    noble   tree. 

found  in  its  perfection  at  moderate  altitude-.  It  has  a  serious  enemy 
in  the  Buprestid,  similar  to,  it*  not  identical  with,  that  which  attacks 
the  red  fir  and  hemlock.  While  I  did  not  have  an  opportunity. 
owing  to  deep  snow,  to  make  extended  observations  regarding  the 
condition  of  this  timber,  it  would  appear  from  what  was  seen  in  the 
Cascade  Reserve  that  many  of  the  finest  tree-  have  died  and  that  an 
unhealthy  condition  prevails. 

11,,  Western  larch. — This  larch,  unlike  its  Eastern  representative, 
grows  chiefly  in  dry  sandy  or  gravelly  soils  and  attains  a  diameter  of  3 
or  4  feet.  It  appears  to  me  to  be  a  very  hardy  tree,  often  retaining 
it-  vitality  for  month-  after  it  is  felled.  It  has  a  common  enemy  in 
Dendroctonw  similis,  which,  as  previously  stated,  is  capable  of  doing 
considerable  harm  to  this  tree  and  the  red  fir.  Many  dead  tree- 
were  found  showing  evidence  of  having  been  killed  by  it,  and  the 
beetles  were  common,  entering  the  living  bark  of  recently  felled  trees 
in  the  vicinity  of  Kootenai.  Idaho.  A  Buprestid  bark  borer,  probably 
Melcmophila,  was  found  in  all  stages  of  the  bark  in  felled  trees,  and 
Scolytus  wvispinosus  was  common  in  the  inner  bark  of  the  tops  and 
branches  of  tree-  felled  in  the  summer  of  L898.  The  number  of  dead 
observed  and  the  common  occurrence  of  dead  branches  on  living 
ones  indicated  that  considerable  damage  had  been  done  by  its  insect 
enemies. 

GENERAL    OBSERVATIONS    <»N     SOME     FOREST     PROBLEMS    OF    THE 

NORTHWEST. 

My  interest  in  forest  subjects  in  general  and  previous  studies  of 
the  forest  conditions  in  West  Virginia  led  me  to  make  some  general 
observations  on  the  forest  problems  of  the  Northwest  which  are  in 

any  way  related  t<>  insect  depredation-.  Buch  as  the  influence  of  farm- 


23 

ing  and  lumbering  methods,  mining  operations,  forest  fixes,  and 
diseases  of  trees. 

Injhhin:  of  farming  )n<th<>(h.  I  found  that,  in  addition  to  the 
girdled  timber  contributing  to  the  multiplication  of  dangerous  insect 
enemies  of  forests,  the  clearings  made  in  the  midst  of  primitive  for- 
ests by  the  settlers  and  farmers  expose  the  trees  on  the  borders  of 
such  clearings  to  abnormal  influences,  which  weaken  the  vitality  of  the 
matured  timber.'  The  destructive  insects  and  their  allies,  breeding  in 
the  girdled  trees,  erne  roe  and  attack  these  weakened  ones,  and  with 
this  additional  material,  and  most  favorable  conditions  for  their  multi- 
plication and  spread  into  the  healthy  forest,  a  trouble  is  often  started 
which  results  in  the  destruction  of  vast  quantities  of  timber. 

Influence  of  lunibermg  methods. — The  abundance  of  timber  in  this 
great  forested  area  and  the  cost  of  transporting  the  products  to  market 
leads  in  most  cases  to  wasteful  lumbering  methods,  only  the  best  timber 
suitable  for  special  purposes  being  taken.  The  remainder,  which  in  a 
short  time  would  be  just  as  valuable  for  other  purposes,  is  left  with 
scarred  trunks,  broken  tops  and  branches,  and  deprived  of  the  pro- 
tective environments  under  which  it  had  developed..  The  ground  is 
strewn  with  tops,  branches,  and  trunks  of  the  felled  timber,  which, 
with  the  injured  standing  trees,  furnish  the  most  attractive  breeding 
places  for  all  bark  and  wood  infesting  insects.  If  the  cutting  is  con- 
tinued from  year  to  year  in  the  same  locality  the  insects,  upon  emerg- 
ing from  the  debris  of  the  old  cuttings,  migrate  to  that  of  the  new,  and 
do  not  invade  the  healthy  or  undisturbed  forests.  If,  on  the  other 
hand,  cutting  is  discontinued  and  the  debris  is  not  destroyed  by  fire, 
there  is  great  danger  of  the  insects,  upon  emerging,  attacking  the 
healthy  timber  in  the  surrounding  forests  and  continuing  their  rav- 
ages there. 

The  relation  of  forest  f/res  to  depredations  by  insects. — This  is  a  sub- 
ject to  which  little  attention  has  heretofore  been  given.  My  observa- 
tions in  the  fire-swept  areas  in  the  Northwest  has,  in  addition  to 
previous  observations  in  West  Virginia,  convinced  me  that  this  is  a 
problem  of  considerable  importance.  Trees  dying  from  injury  by 
fires  furnish  favorable  breeding  places  for  vast  numbers  of  destructive 
and  other  bark  and  wood  infesting  insects.  Those  slightly  injured 
and  weakened  in  vitality  are  prevented  from  recovery  by  the  attack 
of  bark  beetles,  which  are  ever  ready  to  take  advantage  of  any  oppor- 
tunity to  overcome  the  resisting  forces  of  their  favorite  host  plants. 
Thus  the  most  favorable  conditions  are  offered  for  the  multiplication 
of  insect  depredators,  which,  through  their  augmented  power  in 
increased  numbers,  are  capable  of  extending  their  ravages  into  the 
healthy  forests.  Fire  wounds  at  the  bases  of  living  trees  also  lead  to 
serious  trouble  and  losses  of  the  most  valuable  timber.  These  wounds 
give  entrance  to  Cerambycid  and  Buprestid  heartwood  borers,  black 


'24 

ants,  and  wood  decaying  fungi,  ail  of  which  extend  from  year  t<>  year 
their  obscure  yet  destructive  work.  Nor  does  the  trouble  cud  here. 
The  dead  trees  and  decaj  ing  wood  of  the  li\  Lng  ones,  as  indicated  on 
previous  pages,  offer  most  favorable  condition-  for  the  starting  and 
spread  of  forest  fires.  It  is  therefore  plain  that  in  considering  methods 
of  preventing  depredations  by  Insects  those  relating  to  the  prevention 
of  forest  fires  are,  under  certain  conditions,  of  Bpecial  importance. 

In  the  nonreserved  forests,  where  extensive  timber  operation-  arc 
carried  on,  the  prevention  of  forest  lire-  as  a  means  of  controlling 
insect  depredations  is  far  less  Important  than  in  the  reserves.  In  fact 
the  debris  in  cut-over  area-  serves  as  attractive  traps  for  the  insects, 
w  here  they  may  be  effectually  destroy ed,  or  their  migration  to  healthy 
timber  prevented,  by  the  almost  inevitable  conflagrations  which  follow 
these  cuttings.  Therefore  under  such  condition-  it  is  not  so  much  the 
problem  of  prevention  of  fires  as  that  of  their  control  which  should 
receive  attention,  since  if  this  debris  can  be  burned  at  a  time  when  the 
condition-  are  least  favorable  for  the  tire  to  spread  into  the  standing 
timber  the  desired  good,  in  the  destruction  of  insects,  would  be  attained 
and  the  evil  effects  of  the  fires  averted.  ( )n  the  other  hand,  every  pos- 
sible effort  should  be  made  to  prevent  outbreaks  of  tires  in  virgin  and 
reserved  fore-ted  area-,  not  only  to  prevent  the  vast  destruction  by 
fire  alone,  hut  a-  a  precaution  against  destructive  ravages  by  insects. 

Relation  of  insect  enemu  s  of  trees  to  forest  fires*  This  is  a  Bubject  on 
which  nothing  appears  to  have  been  published,  yet  it  requires  only  a 
little  observation  in  the  Western  forest  to  make  it  clear  that  the  trees 
which  have  been  killed  by  insects  furnish,  in  their  fallen  branches, 
standing  and  fallen  partly  decayed  trunks,  and  dry  hark,  a  most  favor- 
able condition  for  the  starting,  rapid  spread,  and  perpetuation  of  forest 
tire-. 

Hi,  relation  of  diseases  of  trees  to  insect  enemies  of  forests.  It  is 
well  known  that  forest  trees  weakened  by  disease  contribute  to  the 
multiplication  of  their  insect  enemies.  It  i-  also  known  that  ins 
will  attack  healthy  trees,  and  thai  diseases  of  the  bark  and  wood  fol- 
low as  a  result  of  such  injuries.  Therefore,  in  the  investigations  of 
unhealthy  conditions  of  forests  it  i-  often  exceedingly  difficult,  with- 
out some  previous  knowledge  of  the  habit-  of  the  diseases  and  insects 
found  associated  with  them,  to  decide  which  i-  to  blame  for  the  pri- 
mary injury.  Our  present  knowledge  of  the  subject,  however,  indi- 
cates that  a-  a  rule  unhealthy  forest  trees,  like  unhealthy  animals. 
present  characteristic  symptoms,  which  indicate  quite  clearly  the  pri- 
mary cause  of  the  trouble.  The  evidence  I  have  been  able  to  gather  in 
the  forests  of  the  Bast  and  Northwest  makes  it  plain  to  me  that,  of  the 
two  causes,  while   many    small    tree-   are   killed   by    root   diseases,   the 

unhealthy  condition  of  the  larger  tree-  i-  more  often  due  to  primary 

attack-  by  insects.       Indeed     it  appear-  that  insects  contribute  more  to 


25 

the  spread  of  fungous  diseases  of  the  bark  and  wood  of  the  main  trunk 
than  do  such  diseases  to  the  spread  and  ravages  of  insects. 

The  most  striking  example  of  insects  contributing  to  the  spread  of 
fungous  diseases  was  observed  in  the  while  fir  throughout  the  region 
traversed;  the  heartwood  of  which  is  commonly  rendered  worthless 

by  decay  as  the  result  of  wounds  in  the    living  bark   made  h\    ScolytUS 

bark  beetles. 

Interrelations  of  forest  fires,  insects,  and  fungous  diseases.-  It  will  be 
seen  from  the  foregoing  references  to  the  relation  of  forest  fires  to 

insect  ravages,  insects  to  forest  fires,  diseases  of  trees  to  insects,  and 
insects  to  fungous  diseases,  that  there  is  a  close  interrelation,  and,  to  a 
certain  extent,  interdependence  of  all  of  these  factors  in  the  destruc- 
tion of  valuable  forest  products.  While  I  had  made  some  observation^ 
along-  this  line  in  the  forests  of  West  Virginia,  I  had  little  conception 
of  the  magnitude  and  importance' of  the  problem  previous  to  my  trip 
through  the  forests  of  the  Northwest,  where  quite  conclusive  evidence 
was  found  that  had  it  not  been  for  previous  depredations  by  insects 
and  consequent  rapid  decay  of  the  standing  and  felled  timber,  far  less 
destruction  by  forest  fires,  or  need  for  trouble  and  expense  in  efforts 
toward  the  prevention  and  control  of  this  prevalent  evil,  would  have 
occurred.  It  was  also  evident  from  the  conditions  observed  in  some 
sections  that  practical  means  of  greatly  mitigating  the  destructive 
effects  of  these  separate  and  combined  causes  of  prevailing  troubles 
could  be  had  through  a  better  knowledge  of  some  of  the  leading- 
features  of  this  problem. 

CONSIDERATION    OF    PREVENTIVES   AND    REMEDIES. 

The  object  of  the  trip  was  to  study  insect  enemies  of  forests  and 
causes  of  prevalent  unhealthy  conditions,  rather  than  the  subject  of 
preventives  and  remedies.  Indeed,  much  additional  and  detailed 
investigation  relative  to  the  life  histories  and  habits  of  the  more 
destructive  enemies,  and  of  the  conditions  which  affect  them  is  neces- 
sary in  order  to  obtain  evidence  on  which  to  base  reliable  conclusions. 

The  fact  that  the  Western  destructive  pine-bark  beetle  is  attracted 
to  girdled  trees,  suggested  girdled  and  felled  trap  trees  as  a  practical 
method  of  preventing  and  checking  destructive  outbreaks  of  this  and 
other  insects  with  similar  habits,  especially  in  forest  reserves,  and  I 
think  some  experiments  should  be  conducted  in  order  to  determine 
whether  or  not  this  would  prove  effectual. 

The  discontinuance,  so  far  as  possible,  of  the  common  practice  of 
settlers  and  farmers  girdling  pine  and  spruce  trees  and  leaving  them 
standing  in  the  clearing  from  year  to  year  was  suggested  by  the  con- 
ditions observed  as  a  most  important  precaution  against  the  multipli- 
cation and  destructive  outbreaks  of  certain  dangerous  enemies  of 
conifers.     On  the  other  hand  if  such  girdled  conifers  could  be  felled 


26 

and  tin-  bark  removed  before  the  broods  of  bark-'beetles  emerge,  vast 
numbers  of  these  pests  would  be  effectually  destroyed. 

The  prevention  and  intelligent  control  of  forest  fires  is  also  believed, 
as  previously  stated,  to  be  a  most  important  precaution  against  the 
extension  of  insect  depredations,  as  is  also  the  prevention  of  insect 
ravages,  and  the  proper  management  of  timber  killed  by  them,  a 
necessary  precaution  against  forest  fires. 

The  introduction  of  natural  enemies  of  destructive  insects  as  a  means 
of  controlling  them  might  prove  effectual  under  certain  favorable  con- 
ditions, l)ut  before  this  or  any  other  method  is  recommended  for  the 
prevention  and  control  of  forest  pests,  each  separate  trouble,  and  the 
attendant  physical  and  other  condition-  prevailing  in  the  region  or 
i  >rest  in  which  it  prevails,  should  he  thoroughly  Btudied. 

SUMMAKl     \M»    RECOMMENDATIONS. 

Before  concluding  this  preliminary  report  it  seems  proper  t<>  call 
attention  to  some  of  the  insects  and  subjects  relating  to  their  destruc- 
tive ravages  which  the  results  of  my  investigation  suggest  a-  the  most 
important  tor  investigation.  The  insects  mentioned  in  the  following 
List  were  found  to  be  of  special  economic  importance  on  account  of 
their  destni(  fcive  habits,  and  therefore  demand  primary  consideration: 

Dend/roctonus  hrevicomis  Lee.,  a  widely  distributed  and  common 
barkbeetle,  destructive  to  the  Western  yellow  pine  and  the  sugar 
pine:  observed  in  California,  Washington,  Oregon,  and  Idaho. 

Dendroctonus  n.  sp.,  a  common  and  destructive  enemy  of  the  white 
pine  and  the  sugar  pine;  observed  in  Oregon  and  Washington,  and 
reported  from  Montana  and  South  Dakota. 

Dend/roctonus  si/miUs  Lee.  a  very  common  and  widely  distributed 
enemy  ^i  the  wy\  fir  and  Western  larch;  observed  in  California. 
( hregon,  and  Idaho. 

Scolytus  j>r<tr,j>s  Lee.  and  closely  allied  species,  one  or  more  of 
which  are  Aery  common,  widely  distributed,  and  destructive  enemies 
of  the  fir:  observed  in  California,  Oregon,  and  Idaho. 

Geometrid  loyrvm*  destructive  to  the  foliage  and  causing  the  death  of 
vast  quantities  of  Tideland  spruce  and  hemlock  in  Clatsop  and  Tilla- 
mook counties,  Oreg.;  the  result  of  it<  work  observed. 

MelcmophUq  drumm/mdi  Kirby,or  a  closely  allied  species,  a  common 
and  destructive  enemj  of  the  red  fir,  hemlock,  and  noble  tin  larvae 
and  work  observed  in  Oregon,  Washington,  and  Idaho. 

Neophasia ?nefiapia Yeld,,  the  pine  butterfly,  a  common  and  d  struc- 
tiveenemy  of  the  Western  yellow  pine  in  Idaho  and  eastern  Washing- 
ton; it>  destructive  work  observed. 

The  first  five  insects  named  in  this  li-t  are  probably  the  live  worst 
insect  enemies  of  the  Western  forest  The  evidence  found  indicates 
that  they  have  caused  the  death  of  manv  million  dollar.-*  worth  of  the 


finest  timber  and  thai  they  are  capable  <>!'  causing  greater  losses  in  the 
future.  Nothing  whatever  seems  t<>  have  been  published  regarding 
the  habits  of  any  of  them,  and  little  or  nothing  was  known  of  their 
economic  importance  previous  to  the  investigation  here  reported. 

The  interrelation  of  forest  fires,  insect  enemies,  diseases  of  t  rees,  and 
human  agencies  in  the  destruction  of  forests,  is  a  problem  of  especial 
importance,  the  investigation  of  which  will,  no  doubt,  yield  most  valu- 
able results. 

I  would  also  suggest  the  importance  of  conducting  experiments  with 
girdled  and  felled  trap  trees  in  some  of  the  forest  reserves  threatened 
by  bark  beetles,  to  determine  their  value  in  preventing  and  controlling 
the  ravages  of  destructive  bark-infesting  insects.  Experiments  in 
partially  burning  dead  timber  and  the  debris  left  by  timber  cutters,  at 
a  time  of  year  when  the  conditions  are  least  favorable  for  its  spread,  is 
also  a  line  of  work  which  seems  to  be  promising  in  results. 

A  study  of  certain  prevailing  physical  conditions  in  the  Northwest 
and  their  relation  to  distribution,  common  or  rare"  occurrences,  and 
destructive  habits  of  the  principal  insect  enemies  of  the  forest,  will 
also  surely  lead  to  results  of  special  interest  and  value. 

In  addition  to  results  of  economic  importance,  the  investigation  of 
the  subjects  mentioned,  involving  as  they  do  technical  studies  of  the 
insects  and  of  broad  problems  relating  to  their  life,  should  lead  to 
valuable  contributions  to  science. 

In  conclusion,  may  I  suggest  that  the  increasing  public  interest  in 
forest  protection,  the  vast  forested  domain  included  in  reserves  and 
national  parks,  the  aggregate  public  and  private  wealth  in  undeveloped 
forest  resources,  and  the  extensive  destruction  of  the  best  timber  each 
year  by  insects  and  related  evils  seem  to  warrant  giving  this  heretofore 
neglected  feature  of  the  forest  problems  of  this  countiy  especial  at- 
tention. It  is  a  line  of  scientific  research  which,  in  consideration  of 
its  relation  to  their  work  and  interests  can  not  fail  to  receive  the 
hearty  support  and  cooperation  of  other  divisions  of  the  public  serv- 
ice— such  as  the  Division  of  Forestry,  the  General  Land  Office,  the 
State  experiment  stations  and  forestry  schools. 


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RSITY  OF  FLORIC 


